Ign:7 http://security.ubuntu.com/ubuntu cosmic-security InReleaseErr:8 http://security.ubuntu.com/ubuntu cosmic-security Release 404 Not Found [IP: 91.189.91.24 80]Reading package lists...E: The repository 'http://archive.ubuntu.com/ubuntu cosmic Release' does not have a Release file.E: The repository 'http://archive.ubuntu.com/ubuntu cosmic-updates Release' does not have a Release file.E: The repository 'http://archive.ubuntu.com/ubuntu cosmic-backports Release' does not have a Release file.E: The repository 'http://security.ubuntu.com/ubuntu cosmic-security Release' does not have a Release file.